MIST

Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

New mailing list for Python in space science

A new mailing list for space scientists who use Python has been founded. Angeline Burrell writes: 

There's been a recent push for more community python development and peer-to-peer support. Much of this is focused in the US at the moment, but as the results of the recent survey showed, MIST scientists are active or interested in python as well. If you would like to become involved, you can join the email list by contacting This email address is being protected from spambots. You need JavaScript enabled to view it..

The mailing list will comprise discussion as well as webinars/telecons from Python users, so the list should be useful for a range of abilities with Python. To join, please email This email address is being protected from spambots. You need JavaScript enabled to view it..

New MIST forum via Slack

In the days of yesteryear, there was a MIST forum provided for members of the MIST community to discuss things in a fashion more immediate and informal than email. It has been some years since the fabled MIST forum was a going concern, and in that time, the MIST Council has technically been in violation of the MIST Charter, which states that

MIST will provide an on-line forum to allow ongoing discussions and the formulation of ideas prior to public dissemination. This forum will be private, visible only to registered members; membership is restricted to active MIST scientists and is offered at the discretion of MIST council chair.

As a result of realising that the Charter mandates the maintenance of a forum, MIST Council have chosen to create a Slack workspace for the MIST community. If you would like to join, please This email address is being protected from spambots. You need JavaScript enabled to view it. specifying the email address you would like to use, and you will be invited to join.

MIST Council election results

The polls have closed, and Oliver Allanson (Reading) and John Coxon (Southampton) have been elected to MIST Council. The full results of 2018’s elections are as follows:

  • Oliver Allanson: 56 votes
  • John Coxon: 100 votes
  • Simon Pope: 27 votes
  • Samuel Wharton: 38 votes
  • Darren Wright: 40 votes

121 people cast two votes, and 19 cast a single vote, for a total of 140 responses. This is a turnout of 32.9% against the MIST mailing list, which comprises 426 eligible voters.

The chair of MIST Council, Ian McCrea, said:

I would like to congratulate John on his re-election to MIST Council and to congratulate Oliver on his election – we look forward to you joining us at our next meeting. To the unsuccessful candidates, I would like to say a sincere thank you for taking part and for your interest in being part of MIST Council. Obviously only two candidates can be successful in any given year, but there are elections every year and we hope that you will not be discouraged from standing again at a future date.

MIST Council would like to express their thanks and appreciation to Luke Barnard who is leaving MIST Council, and whose contributions over the last three years have been invaluable. We would also like to thank Q Stanley for handling the technical aspects of the election.

Astronomy/Solar System Advisory Panels call for priority projects

The Astronomy and Solar System Advisory Panels have been asked to identify a few priority projects, comprising 'large scale' (>£50M), ‘medium scale’ (£10-50M) and ‘small scale’ (<£10M) projects that can be started within the next 6 years. The outline business cases put forward by the community will be considered by STFC’s Executive Board and Science Board in September. We will then work with the community and UKRI to identify the best way of taking these ideas forward. 

Interested parties should summarize their ideas for priority projects using the template provided. Only those projects considered to be the most exciting and highest priority (by the Advisory Panels) will be asked to develop an outline business case. Please email your project summary to This email address is being protected from spambots. You need JavaScript enabled to view it. (Astronomy) or This email address is being protected from spambots. You need JavaScript enabled to view it. (Solar System). If your project has overlap with both astronomy and solar system, then please indicate this in your summary and send to both panels. The deadline is Wednesday 18 July 2018. If you have any questions regarding remit, format or submission, please feel free to contact the relevant Advisory Panel.

Jonathan Eastwood wrote, in his email to the MIST mailing list:

STFC has launched a consultation with research communities, designed to identify new world class science and technology proposals for potential future investment. The aim is to develop an ambitious portfolio of outline business cases for priority projects that relate to our strategic scientific and research infrastructure objectives, covering our remit, and driven by our communities… the scope of the projects is very broad – what is needed are exciting and ambitious scientific projects within the broad remit of astronomy and solar system science. Funds for estates and campus development are out of scope, and projects should not be an uplift to the grant/fellowship lines. This exercise is not part of the Evaluation of Astronomy which STFC will undertake in the Autumn (part of its assessment of the wider astronomy, particle and nuclear physics programmes), but projects identified here will be forwarded to that exercise to ensure information is not lost.

MIST Council would like to urge members of the MIST community to engage with this exercise in order to make sure that MIST science is well-represented in STFC strategy in the future.

Petition to eliminate harassment and bullying

MIST council is committed to fostering an open and inclusive scientific environment.

Many people will have seen the recent reports of bullying and harassment in Universities are becoming more and more widespread. In one of many steps to highlight the need for these actions to stop, an open letter and petition has been prepared by members of the wider community, including faculty from Imperial, UCL, and other UK and international institutions. This cross-institute example underlines the importance of eliminating harassment and bullying from the university and research environments. If you wish to sign the petition, you can find it by clicking here.

Our community is a big part of the RAS, which has a Code of Conduct and a Diversity, Equality and Inclusion Policy that we must adhere to:

  1. Promoting an inclusive environment for all.
    2. Promoting equality of opportunity.
    3. Welcoming applications from all backgrounds.
    4. Supporting and developing careers for all.
    5. Recruiting and promoting staff based on merit, rather than absence or presence of underrepresented characteristics.

We would strongly encourage our community to continue to participate in eradicating these issues from our scientific and every day lives.

Untangling the periodic ‘flapping’ and ‘breathing’ behaviour of Saturn’s equatorial magnetosphere

By Arianna Sorba, Department of Physics and Astronomy, University College London, UK.

At Saturn, the planet’s rotation axis and the dipole axis are aligned to within 0.01° [Dougherty et al., 2018], and so the magnetosphere’s magnetic field should be extremely azimuthally symmetric. However the Cassini space mission, which orbited Saturn from 2004-2017, observed mysterious periodic variations in the magnetic field at a period close to the planetary rotation rate. These observations suggested that the outer magnetosphere’s equatorial current sheet was `flapping’ above and below the rotational equator once per planetary rotation, to a first approximation acting like a rotating, tilted disc [Arridge et al., 2011].

However this ‘flapping’ picture does not fully explain the observed magnetic field periodicities. More recently, some studies have suggested the magnetosphere may also display ‘breathing’ behaviour; a periodic large-scale compression and expansion of the system, associated with a thickening and thinning of the current sheet [Ramer et al., 2016, Thomsen et al., 2017]. In Sorba et al. [2018], we investigate these two dynamic behaviours in tandem by combining a geometric model of a tilted and rippled current sheet, with a force-balance model of Saturn’s magnetodisc. We vary the magnetodisc model system size with longitude to simulate the breathing behaviour, and find that models that include this behaviour agree better with the observations than the flapping only models. This can be seen in the figure below, which shows that for an example Cassini orbit, both the amplitude and phase of the magnetic field variations are better characterised by the flapping and breathing model, especially for the meridional component (middle panel).

The underlying cause of this periodic dynamical behaviour is still an area of active research, but is thought to be due to two hemispheric magnetic field perturbations rotating at different rates. The study by Sorba et al. [2018] provides a basis for understanding the complex relationship between these perturbations and the observed current sheet dynamics.

For more information, please see the paper below:

Sorba, A.M., N. Achilleos, P. Guio, C.S. Arridge, N. Sergis, and M.K. Dougherty. (2018), The periodic flapping and breathing of Saturn's magnetodisk during equinox, J. Geophys. Res. Space Physics, 123. https://doi.org/10.1029/2018JA025764

Figure: Radial (a), meridional (b), and azimuthal (c) components of the magnetic field measured by Cassini along Rev 120 Inbound. Magnetometer data shown in black, flapping only model shown in red, and flapping and breathing model shown in blue. Annotation labels underneath the time axis give the cylindrical radial distance of Cassini from the planet centre, and Saturn magnetic local time.